By default, when a scheduled report is configured to export the result into a CSV file, the encoding is set to Unicode and, while creating the report, there is no further changes available in regard of encoding:
Client Automation - All supported versions
In order to do change the encoding of the CSV file, the following Config Policy can be changed:
DSM -> Administration Console -> CSV export Data Format
The available values are Unicode and ANSI.
Is recommended to create a new Config Policy, different than the default, and change the value there and apply that policy to the Domain Manager only.